Florence is forecast to make landfall in North Carolina late Thursday as a major hurricane and subject the region to high winds and heavy rain.

The governor of neighbouring North Carolina also ordered an evacuation of the Outer Banks, barrier islands that are a popular tourist destination, and parts of coastal Dare County, while a state of emergency was declared in Virginia.

With Hurricane Florence spinning through the Atlantic Ocean and threatening to slam into SC later this week, Gov. Henry McMaster ordered mandatory evacuations for the state's entire coastline beginning at noon Tuesday.

Early on Tuesday, Florence was centred about 975 miles east-south-east of Cape Fear, North Carolina, and moving west-north-west at almost 15mph.

Kottlowski is concerned that Florence will slow down and possibly stall near or inland of the coast, potentially leading to a life-threatening flooding situation.

Florence is now one of three hurricanes spinning in the Atlantic Ocean, along with Helene and Isaac.

Just in case anyone thought the post and event was a genuine storm deterrent method, he added: "Note: do not actually discharge firearms into the air".

Kevin Orth loads sandbags into cars on Milford Street as he helps residents prepare for Hurricane Florence on Monday in Charleston, S.C.

"But if you put a foot or 2 - or maybe in some isolated places more - of rain over hills and mountains, you have a very different kind of problem, which is really more unsafe than the flat situation, as bad as that was", he said. McMaster estimated about 1 million residents would be fleeing the coast before Florence's arrival.

"The bottom line is that there is increasing confidence that Florence will be a large and extremely unsafe hurricane, regardless of its exact intensity", he said.

The Miami-based center says the storm's center was located about 410 miles (660 kilometers) south of Bermuda and about 975 miles (1570 kilometers) east-southeast of Cape Fear, North Carolina.

President Donald Trump tweeted the federal government stood prepared to assist the governors of the USA states affected.

It is then forecast to close in on North or SC on Thursday, hitting a stretch of coastline that is vulnerable to rising sea levels due to climate change.

Evacuation shelter locations for those evacuating from the state's northern and central coastal counties will be available on scemd.org, McMaster said. South Carolina Gov. Henry McMaster also suspended his campaign and asked President Donald Trump for a federal emergency declaration.

This happened a year ago, too, when Hurricane Jose and Tropical Storms Maria and Lee were churning at the same time. Obviously it's a big storm with high winds.